Here's an interesting wrinkle. It appears that below a certain rotational speed the VR signal becomes unreliable. This makes perfect sense if you think about it since it relies on a somewhat similar triggering method as the scope does, which is to say, triggering a voltage state change from 0 to 12v and back depending on the transition of the signal generated by the tooth. The output signal remains a 12v square wave and this tells us that there is indeed signal processing going on in the sensor. It is not a simple VR pickup. If it were the voltage and waveform would vary with the speed and it does not, at least to any significant degree. This further tells us that the pickup probably uses the rear pattern to blank out noise or unwanted pulses from the 24 tooth wheel on the front.
BUT that also means that detecting the condition changes using a multimeter and turning the crankshaft by hand is likely to prove unreliable or at least inconsistent.
I see this on the mockup. Giving it a moderately slow spin through 1/4 of the rotation gives a good solid pulse train but I can slowly rotate it through any number of teeth at about the speed you'd be able to do with a wrench on the crankshaft without any voltage change at all.
I've not tested the cam sensor yet to see if it acts in a similar way.
Jim
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